21720215

素因数分解:

$5^1\times {\mathrm{11}}^1\times {\mathrm{557}}^1\times {\mathrm{709}}^1$

素因数の和:1282

約数の個数: 16

約数和(自身を含む): 28524960

約数和(自身を除く): 6804745

約数列:

[1, 5, 11, 55, 557, 709, 2785, 3545, 6127, 7799, 30635, 38995, 394913, 1974565, 4344043, 21720215]

約数ペア:

[(1, 21720215), (5, 4344043), (11, 1974565), (55, 394913), (557, 38995), (709, 30635), (2785, 7799), (3545, 6127)]